Carpet sweeper with pivotable brush support



Nov. 3, 1953 E. R. SMITH CARPET SWEEPER WITH PIVOTABLE BRUSH SUPPORT Filed Feb. 9, 1948 3 Sheets-Sheet l NNK w wm M S. T n 1R E a. m. E.. m A M .qu 9% a M View ATTORNEY NV 3, 1953 E. R. sMn-H 2,657,407

CARBETFSWEEPER WITH PIVOTABLE: BRUSH SUPPORT Filed Feb. 9, 1948 3 Sheets-Sheet 2 INVENTOR. ERZE SMITH /MM l A TNE Y Nov. 3, 1953 E. R. SMITH 2,657,407

CARPET swr-:EPER WITH PIVOTABLE BRusHsUPPoRT Fil-ed Feb. 9. 1948 5 Sheets-Sheet 3 I6 "3 ATTORNEY Patented Nov. 3, 1953 OFFICE CARPET SWEEPER WITH PIVOTABLE BRUSH SUPPORT Earle R. Smith, Alhambra, Calif., assigner to Edna Cambell Smith Application February 9, 1948, Serial No. 7,054

9 Claims.

This invention relates to improvements in carpet sweepers. It relates particularly to improvements in the suspension of carpet sweepers and to the mechanical relationship between the Wheels and the brush. Further, the invention relates to various improvements in stabilization and control of carpet sweepers made possible by the improvements in brush and wheel operations.

Conventional carpet sweepers comprise a casing supported at either end by a pair of laterally spaced wheels, and operable by an extended handle connected to the casing by' a U-shaped bail. A brush is rotatably mounted on the longitudinal axis of the casing, the opposite ends of the brush axle extending between the opposite pairs of wheels and in frictional engagement therewith. Motion of the sweeper over a carpet causes the wheels to rotate thereby imparting rotary motion to the brush. A pair of dust pans disposed in the housing on either side of the brush, collect rthe sweepings as the brush rotates. To permit withdrawal and insertion of the brush, the wheels are suspended in laterally movable manner so that they may be spread. A spring Y urges the wheels against the brush axle and tends to prevent spreading of the wheels when the sweeper is in operation. f

In early sweepers the brush was journaled to the casing and was not free to move laterally during operation. As a result of the resilient mounting, the trailing wheels tended to spread so as to impair the frictional engagement with the brush axle. In an earlier Patent No. 2,166,977, l disclosed means whereby the brush could shift laterally along with the wheels so asv to provide positive drive by all of the wheels. The present invention provides improvements in this lateral brush shifting means.

Partly in consequence of the so-called oating wheel suspension which results in a shift of the support points, the distribution of downward pressure on the sweeper case varies with the direction of travel of the sweeper. Thus the pressure on the leading wheels on the floor and against the brush pulley is generally greater than the pressure on the trailing wheels. stabilizing means are provided in the sweeper of the present invention which equalize this downward thrust regardless of the direction of travel.

To increase the utility of carpet sweepers of the type described, means are generally provided to vary the relative elevation of the brush with respect to the wheels. For thick rugs, for example, it is desirable to elevate the brush with respect to the wheels and correlatively with respect to the floor so as to reduce the resistance to travel. The converse is true when sweeping thin rugs. In my Patent No. 2,239,276, I describe a brush adjusting mechanism whereby the brush' may be raised and lowered. The mechanism there described is particularly adapted to use in the sweeper described in my previously mentioned patent wherein the brush is free to move laterally, so that the axles of the wheels and the brush shift as a unit upon changing the direction of sweeping.

In the present invention, I provide an'improved brush shifting means and I also provide improved means for adjusting the relative positions of the wheels and the brush. Although the improved adjusting means are adapted to cooperate with the improved shifting means, they are also applicable to other forms of carpet sweepers. The adjusting means as hereafter more fully described, may take several forms. One such form involves positive vertical displacement of the brush by means of a cam on the bail and a counteracting spring. Another means, of which several embodiments are illustrated, involves the positive displacement of the wheels by means of a cam on the bail and a counteracting spring. A third adjusting means utilizes the tendency of the brush to seek its own level, making provision at the same time for the improved lateral displacement of the brush asherein set forth.

Other improved features of the carpet sweeper of the invention will become apparent from the following detailed description.

In one embodiment, my improved carpet sweeper comprises a casing having floor wheels arranged in pairs at opposite ends thereof and rotatable from separate hangers mounted to the ends of the casing in laterally pivotal and vertically displaceable relationship. A rotary brush extends the length of the casing and is provided with a pair of pulleys, one at each end thereof, each pulley being in frictional engagement with the corresponding pair of ground wheels. An elongated handle is affixed to the casing by means of a bail having two legs pivotally aiiixed at opposite ends of the casing. An elongated spring, hereinafter referred to as the stabilizer spring, is mounted on each end of the chassis. The stabilizer spring is secured to the front and rear of the end member and bows upwardly in the center. The bail depresses the central portion of each of the springs adjacent the point of attachment of the bail to the casing thereby distributing the downward thrust equally to the front and rear of the casing.

A cover plate is aiiXed to each end of the casing and is spaced therefrom to form a housing for the wheels and brush pulleys. Each of the cover plates carries a pivotally mounted tongue to which the opposite ends of the rotary brush are journalled. The pivoting of the opposed tongues permits lateral motion of the brush in unison with the lateral displacement of the ground wheels. The tongues may be sprung away from the casing to permit insertion and retraction of the rotary brush.

In one embodiment of the invention each tongue is provided with restricted vertical freedom whereby the elevation of the brush with respect to the wheels may be adjusted by means hereinafter described. In another embodiment of the invention means are provided fory adjusting the elevation of the wheels, and in still another embodiment means are provided for simultaneously adjusting relative positions of both the brush and the wheels. The adjustment in this latter instant is in opposite directions so that the absolute displacement of either the wheels or the brush for a given relative displacement is onehalf that required ii all the adjustment is accomplished through displacement ofl one or the other.

The foregoing and other features of the invention will be more clearly understood from the following detailed description thereof taken in relation to the accompanying drawing in which:

Fig. 1 is a side elevation of one sweeper according to the invention;

Fig. 2 is a sectional elevation taken on the line 2-2 of Fig. 1;

Fig. 3 is a side elevation of the central' portion of one of the end plates of the sweeper of Fig. 1 with certain features shownin phantom so as to permit illustration of other features;

Fig. 4 is an. end elevation of the sweeper oi Fig. 1 with the cover plate removed to show the wheel mounting, the bale mounting and the stabilizer spring;

Fig. 5 is a partial elevation of a. simplied means of brush mounting taken on the line 5 5 of Fig. 6;

Fig. 6 is a partialV sectionall elevation of this simplined mounting means;

Fig. '7 is a sectional elevation similar to Fig. 2 showing an alternative formy of the invention;

Fig. 8 is an elevation taken on the line 8 8 of Fig. 7

Fig. 9 is a detailed view of one end of the bail member showing the means of engagement thereof with the stabilizer spring;

Fig. 10 is an end elevation of another embodiment of the invention with the cover plate removed to show the wheel mounting and means for raising and lowering the wheel;

Fig. 11 is an elevation looking toward the inside face of a cover plate used in an alternative embodiment of the invention showing means for raising` and lowering both the brush and the wheel;

Fig. 12 is an end elevation of another embodiment of the invention with the cover plate removed to show an alternative form of wheel mounting; and

Fig. 12A is a section taken on the line I2A--I 2A of Fig. 12.

The carpet sweeper of my invention comprises a casing C which includes an endv plate IU, an identical opposite end plate (not shown), and a cover plate I2 spaced from the end plate III and a second cover plate (not shown) spaced from the opposite end plate (not shown). The casing 4 is supported on two pairs of floor wheels, the wheels I4, I5, situated between the end II) and a cover plate I2 being shown in the drawing. Throughout the description of the invention, it is t0 be understood that the arrangement of wheels and associated mechanisms at one end of the sweeper is identical to that at the opposite end and description of one will sumce for both.

As best shown in Fig. '4, which is an end view of the sweeper of Fig. 1, wherein the cover plate I2 has been removed and a portion of the wheels have been cut. away, the wheels III, I5 are rotatably mounted to the end plate by means of hangers I6, I'I respectively. The hangers I6 and I' are pivotal'ly'mounted to the pintles I8, I9 respectively affixed to the end III. The hanger I6 is slotted at 2U. to permit Vertical as well as pivotable motion of the hanger. The hanger I'I is similarly constructed. The wheels are journalled to the lower portions of the respective hangers by means of axles 22, 23 respectively. A spring 25 anchored to the end Illv at 2E and 21 and attached at opposite ends to the axles 22, 23 of the two wheels urges the wheels inwardly against a pulley 30 formed on one end of an axle SI of a rotary brush 32. Rotation of the wheels Idv and I5 causes rotation of the brush 32 by frictional engagement of the wheels with the pulley 39. Pivotable mounting of the wheels is necessary so that they may be spread during insertion of the brush.

As best shown in Fig. 2, the axle SI of the brush 32 is mounted to a tongue 34. The tongue 3S is pivotally mounted to the cover plate I2 on a pintle 36 rigidly afxed to the tongue and rotatably riveted to the cover plate I2. The cover plate I2 is inset at 38 and slotted at 39 in the ofi-set portion separating the inset 38 from the rest of the cover plate. The tongue 34, which is pivotally mounted at its upper end against the inner face of the plate I2 projects through the slot 39 and lies against the outer face of the plate I2` below the slot 39 and in the inset portion 38. To. permit insertion and withdrawal of the brush 32 the tongue 34 may be sprung away from the plate I2. A rubber bumper le ciroumscribes the casing and cover plate, and is sufficiently elastic to permit iiexing of the tongues.

The axle 3l of the brush is riveted to the tongue 34 through a laterally elongated slot I4 (see Fig. 3). The pintle 36, to which the tongue is pivoted is riveted through the. slot li'l. in the cover plate. The slot 44 in the cover plate is elongated horizontally and the slot il vertically. The latter slot permits vertical displacement of the tongue and the lower slot permits lateral displacement of the tongue which'rotates about the pivot point, i. e. the pintle 36 projecting through the plate I2.

In the embodiment here shown, a spring (see Fig. 1) anchored to the inside face of the cover plate I2 at 5 I and52 crosses over the pintle 35 and urges the. tongue 3d downwardly. The inner end of the pintle is provided with the collar 54 which acts as a retainer for the spring 5I).

In this embodiment of the invention the brush 32 is free to move laterally with the lateral motion of the wheels I4 and I5 andis free to find itsv own level by vertical displacement of the tongue 34 which is capable of simultaneous ver tical and angular displacement. The downward thrust exerted on the carpet sweeper will determine in part the elevation of the brush.

An elongated handle @D is affixed to the center of a U-shaped' bail 5I. The leg @IA of the bail is pivotally mounted to the end III by'means of a pintle -63 projecting inwardly from the leg SIA. A corresponding leg (not shown) of the bail is similarly pivotally mounted to the opposite end of the case. The lower end of the bail leg GIA to which the pintle 63'is mounted is provided With an inwardly projecting lip 66'which rides on a stabilizer spring 63. rIhe stabilizer spring 68 is slidably anchored to the end member I at 10, and is bent at BBA to provide stationary but removable anchorage at 69.

The lip 66 is shaped so as to exert a substantially uniform downward thrust on the central section of the stabilizer spring throughout the greater portion of the radius of rotation of the bail. When the bail is pivoted to a so-called rest position as indicated by the dotted lines in Fig. 4, the thrust on the stabilizer 63 is substantially released thereby permitting it to spring back to its rest position likewise indicated by dotted lines in Fig. 4. The lip 66, shown in detail in Fig. 9, is shaped in the form of a triple curve. It is apparent that in any position but the direct vertical position, shown in Fig. 4, the lip 56 will contact the spring 6% at only one place on its curvilinear surface, the curve being such that the pressure on the spring 63 is substantially constant except at the extreme points of angular displacement of the bail. At the vertical position however, the lip 65 contacts the spring 68 at the points 66A and 66B serving to resist continued rotation of the bail and handle. This feature acts as a catch whereby the handle will stay in vthe vertical position shown in Fig. 4 until it is purposely changed. This feature is desirable when the use of the sweeper is temporarily interrupted for some reason. The handle will remain in vertical position until manually rotated therefrom.

The stabilizer spring 63 and its cooperative relationship to the bail 6| is an important feature of the invention and serves to cooperate with the laterally shifting 'brush to produce more efcient and more wear resistant operation of the sweeper. While the lateral shift of the brush prevents uneven wear of the Awheels on the brush pulleys; to a certain extent the stabalization of the downward thrust on the sweeper further increases this Wear resistance by equalizing the thrust on the wheels so as to equalize the wear on the wheel axle and also to provide positive drive of the pulley 3l by each of the wheels.

In the foregoing and following embodiments of the invention the sweeper case is illustrated as one of the various types of cases disclosed in my co-pending application SerialNo. 7,055, filed February 9, 1948, entitled Carpet Sweeper, and

the construction of the case itself` being separate and distinct from the mechanisms herein described forms no part of the present invention. Description thereof is Vtherefore omitted.

A simplined form of brush mounting to be used in cheaper models in conjunction with the vertically and laterally shifting wheels is shown in Figs. 5 and 6. In this embodiment the cover plate I2 (Figs. l and 2) is replaced by a semiflexible metal strap 55. mounted on the inside face of the strap provides a laterally elongated socket in which the brush axle 58 is housed. The axle 58 is formed by extending the body 58A through the pulley 3U shown engaged with the ground wheel I4. rubber bumper @il extends around the outside of the strap 56 and is sufliciently resilient to permit removal of the brush by flexing the strap outwardly. In this modification of the invention The A channel cleatV 51 I greater extent than when the cam 5 the brush is free to shift laterally with the Wheels; the axle 58 riding in thev socket 51. Vertical shifting of the brush relative to the wheels is dependent upon absolute vertical displacement of the Wheel hangers determinable by the thrust applied on the sweeper handle.

A modification of the invention is shown in sectional elevation in Fig, 7 and in partial elevation in Fig. 8. This embodiment provides for positive adjustment of the relative elevation of the brush and the wheel by manipulation of the handle, and thus diifers from the foregoing em bodiments which provided for oating self-seeking adjustment of the brush or wheels. In the sweeper shown in Figs. 7 and 8, a bail 10 is pivotally affixed to end 'Il of the sweeper casing 12. The bail 10 is pivotally ailixed to the end member 1| by means of a pintle 14 and carries an inwardly extending lip 15, similar to the lip 66 in the foregoing embodiment, which exerts a pressure on a stabilizer spring 16. A brush 'I8 is mounted on the longitudinal axis of the case as in the foregoing embodiment and is provided withV a pulley T9 which is in frictional engagement between a pair of ground wheels of which the Wheel 8E) may be seen. The wheels and brush pulley are contained in a housing formed between the end 1l and a cover plate 82, and the brush is rotatable on pintle 84 riveted to a tongue B6 and slidable in a groove 88 in thecover plate. The tongue 8S which is free to pivot in a tapered indentation 9|] in the cover plate is pivotally mounted at its upper end to the cover plate by the pintle 92 which in this embodiment vis rigidly aixed to the cover plate and slidably riveted to the tongue 84. The tongue carries an inwardly projecting pin 94 hereinafter referred to as a cam pin under which a spring 96 (see Fig. 8) projects so as to urge the tongue 86 up- The bail 10 carries a cam |09 spaced from the bail on the shaft |02. The cam |00 has a curvilinear lower surface I 00A which rides on the cam pin 911.A The curvilinear surface IUOA is eccentric with respect to the axis of rotation of the cam so that the displacement of the cam pin by the cam varies as a function of the angular rotation of the bail 10. With reference to Fig. 8, as the cam lll is rotated clockwise about its axle I 02, the cam pin 94 will be depressed to a is rotated counter-clockwise.

In this embodiment of the invention the relative elevation of the wheels and the rotary brush is positively determined by pivoting the bail towards one side or the other of the sweeper.

The pintle 92, rigidly aixed to the cover plate 82, differs from the pintle 6i; in the foregoing embodiment which is rigidly affixed to the tongue and slidably riveted to the cover plate. Vertical displacement of the tongue is accomplished by providing a vertically elongated slot UIQ therein through which the pintle S52 is riveted by the cleat 92A which permits the tongue to oscillate. Thus the lateral shifting of the brush simultaneously with the corresponding shift of the wheels is accomplished in the same manner as in the foregoing embodiment but the vertical adjustment of the brush is positively determined rather than being left to vagaries of changing downward force.

As above indicated, the adjustment of the relative elevation of the brush with respect to the wheels may be accomplished through vertical shifting of the wheels rather than the brush, In

any 'case the shifting of the wheel or the brush takes place with reference to the case itself whereby the relative elevation of the two is changed.

In Fig. I I have shown one means. of varying the absolute placement of the wheels with respect to the case thus varying the relative positioning of the wheels with respect to the brush. In the embodiment shown in Fig. l0 which is a side elevation of a sweeper casing having an end member |68', the wheels ||0, are pivotally mounted at' the lower end of vertical hangers i 2, H3 respectively. rlhe hangers are in turn pivotally mounted to' laterally disposed support arms |-|'4, |'|5 respectively. The support arms H4, H5 are pivotally mounted to the casing end |88 at |`|6 and respectively and are pivotally joined together attheir innermost ends by a pin'l'26 journalled through the two.

The bail arm |22 which is provided with a lip |24 engaging a stabilizer spring |25 in the mannerL heretofore described is also provided with a cam |25 which, engages on a roller |28 mounted on the pin |26. The bearing surface |25A of the cam |26 is eccentric with the axis of rotation of the bail leg |22 so that rotation thereof will displace the roller |28 downwardly to a degree depending upon the angular positioning of the bail |22. Since downward displacement of the roller will result in upward displacement oi the floor wheels a spring |129 anchored to the end |08 engages the wheel axles so as to urge them downwardly as well as inwardly against the brush pulleyv (not shown). In this embodiment of the inventicn'the rotary brush (not shown), may be journ'alled to the cover plates (not shown) in vertically fixed relationship, inasmuch as the relative elevation of the brush and wheels is determined by vertical displacement of the wheels with respect to the case.

An alternative means of adjustment of the relative elevation of the wheel and brush is shown in Fig. l1 which is an elevation of the inside of a cover plate adapted to be aixed in the manner above described to the end of a sweeper casing. In this embodiment ground wheels |36, |3| are rotatably mounted on the ends of hangers |32, |33 respectively which are rotatably and slidably mounted on pintles |34, |35 respectively projecting inwardly from the cover plate |36. A brush mounting tongue |38 is pivotally mounted at its upper end to the inner face of the cover plate |36 by a pintle (not shown) and. extends downwardly throughV a slot |39 and along the outside face of a frusto-triangular inset |40. The tongue |38 carries a cam pin |42 as in the embodiment shown in Fig. 1 which is urged upwardly by a spring |44 anchored at |45 and |46 to the end plate |28. A cam |48 carried on a bail leg (not shown) by a shaft |159 has a lower curvilinear surface |48A which rides on the cam pin |42 and determines the elevation of the cam pin with respect to the cover plate by the angular placement of the bail leg.

A pintle |52 projecting inwardly from the tongue |38 passes through longitudinally elongated slots |53, |54 formed in the inner end cf the hangers |32, |33 respectively. Vertical displacement of the tongue |38 by means of the cam |49 results in a like vertical displacement of the rotary brush (not shown) and a converse vertical displacement of the ground wheels |36, |3| `(assuming the pintles |34, |35 are centrally '|66 on pivot pins |66, |61 respectively.

given relative displacement between the ground wheels and the rotary brush only half as great a vertical displacement of the tongue |38 is required.

Another means of accomplishing the absolute adjustment of the ground wheels and thus the relative adjustment of the wheels, with respect to the brush, is shown in Fig. 12 which is an elevation of thev end of a sweeper with the cover plate removed and Fig. 12A which is a section taken on the line |2'A-|2A of Fig. l2. In this embodiment ground wheels ISI', |62 are rotatably mounted on the lower end of hangers |63, 61|y respectively which are pivotally mounted to the casing end A plate |10 having longitudinally elongated slots |111, |12 at opposite ends thereof is mounted to the end on the same pivot pins |66, |61 and isfree to slide thereon to the extent of the length of the slots |1|, |12.

The plate |10 is provided at opposite ends with a pair of notches |14, |15 and |18, |19 respectively in the upper edge thereof. Each of the hangers |63, |64 carries a transverse pin |63A, |6iA respectively hereinafterreferred to as the traveling pins. The traveling pins project 4from both faces of the hangers, one end thereof rest'- ing in the notches in the plate |16 and the opposite end thereof riding in cam shaped receptacles |11, |66 in the end |601 of the casing.

The opposite pairs of notches in the plate |18 are inversely arranged so that the two traveling pins will rest simultaneously in notches of corresponding depth.

Spaced from the center of the plater |16 are a pair of arcuate ears |82, |83. The bail |85, pivotally mounted aty |86 to the end of the casing, is provided with an elongated extension |88 which engages one or the other of the ears |82, |83. In the position shown in Fig'. l2 rotation of the upper part of the bail about the point |86 in a countercl'ockwise direction will cause the plate |10 to travel towards the right whereby the inner ends of the traveling pins |63A, |64A will be elevated along the inclined edges |11A, |86A of the respective receptacles until the peak between the deep and shallow notches at each end of the plate passes under the respective pin. The pins will then drop into the corresponding shallow notches |14, |18. In this position the Wheels |6|, |62 will be elevated with respect to the case an amount equal to the diii'erential in the depths between the deeper and the shallower notches. Thereafter rotation of the bail |85 in the opposite or clockwise direction will operate on the ear |82 to shift the plate |10 in the reverse direction to the position shown in the drawing. In this reverse shift the thrust on the plate will push the traveling pins up the inclined edges |11B, |86B so as to permit the peaks between the two notches in the respective pairs to pass thereunder. Thereafter the pins will fall into the positions shown in Fig. 12.

The hangersl |62 and |64 which pivot on the pins |66, |61 and ride up and down in accordance with the displacement of the respective traveling pins are provided with the enlarged circular openings |96, |9| respectively to permit vertical and lateral displacement of the hanger with respect to the pivot pin. In this embodiment of the invention a rotary brush (not shown) may be journaled to a tongue pivotally mounted to a cover plate in the manner described spaced between the hanger ends). Thus for any above,

It'is apparent that the necessary force, as applied 4by the lateral thrust on the sliding plate |10, to lift the traveling pins up the inclined edges of the cam shaped receptacles in the casing' is considerably less than that which would be required to raise the pins along a vertical edge. This f orce is applied against the pin bythe inclined edges of the sliding plate. l have found that the horizontal component thereof is such as to render, perpendicular displacement of the pin virtually impossible. This horizontal component is of' course a function of the angle of the sides of the notches and can be reduced by decreasing this angle of slope. However, the permissible angle of slope is a function of the obtainable lateral displacement of the plate II. I have found that the provision of the cam shaped receptacles in the housing which provide inclined edges upon which the pins may' travel is the most practical method of obtaining the verticaldisplacement of the traveling pins, vand consequently the hangers, in this type of mechanical movement.

I have described and illustrated animproved carpet sweeper wherein the efficiency and ease of operation have been increased and at the same time the mechanical durability thereof hasbeen extended. This is accomplished by the provision of a laterally shifting brush which in cooperation with means for stabilizing the downward thrust throughout the area of the bottom surface of the casing provides for a constant frictional engagement between the wheels and the iloor and between the wheels and the brush pulleys which rotates responsive to the rotation of the wheels. Many modifications in the design of the sweeper and the Vindividual elements thereof Vmay occur to' those skilled in the art without departing from the scope of the invention as set forth.

1 claim:

1. A carpet sweeper comprising floor wheels arranged in pairs at opposite ends of a casing androtatable on laterally pivotal'and vertically displaceable hangers, a rotary brush mounted in the casing, a pulley on 'each end of the brush between the wheels of each pair and in driving contact therewith, means for urging the respective wheels of each pair toward the other and into contact with the pulley disposed Y,

therebetween, a bail having a separate leg pivotally mounted tol'each end of: the casing and supporting an elongated handle, a separate stabilizer spring connected to each end of 4the casing at points adjacent the leading and trailingedges A thereof, means forming la part of each lleg of ing contact therewith, means for urging the respective wheels of each pair toward the other and into contact withithe pulley disposed therebetween, a bail having a separate leg pivotally mounted to each end of the casing and supporting an elongated handle, a stabilizer spring anchored at .the two sides of each end of the casing, means forming a part of each leg of the bail for exerting a downward thrust on the central portion of each stabilizer spring, a cover plate aflixed to each end of the casing and forming a housing with the ends of the casing for the wheels and pulley, a tongue pivotally mounted in vertically slidable relationship to the upper part of each of said cover plates and extending downwardly therefrom to a point below the axis of rotation of the brush, the brush being journaled at either end to the corresponding tongue, each cover plate having a tapered inset portion in which the tongue mounted thereto is free to pivot, and means associated with said bail for changing the relative vertical positions of the Wheels and brush.

3. A carpet sweeper comprising floor wheels arranged in pairs at opposite ends of a casing and rotatable on laterally pivotal and vertically displaceable wheel hangers, a rotary brush mounted in the casing, a pulley on each end of the brush between the wheels of each pair and in driving Contact therewith, means for urging the respective wheels of each pair toward the other and into contact with the pulley disposed therebetween, a bail having a separate leg pivotally mounted to each end of the casing and supporting an elongated handle, a stabilizer spring anchored at the two sides of each end of the casing, means forming a part of each leg of the bail for exerting a downward thrust on the central portion of each stabilizer spring, a cover plate affixed to each end of 'the cas'ing and forming a housing withthe ends of thecasing for the wheels and pulley,'a tongue vpivotally-mountedl in vertically slidable relationship on the inside face of each of said cover plates and adjacent the upper edgeY thereof, each tongue extending downwardly through the cover plate to a point below the Y axis of rotation of the brush, each cover plate ally mounted'in vertically slidable relationship y to the upper part of each of said cover plates and extendingdownwardly therefrom to a point below the axis of rotation of the brush, the brush being journaled at either end to the corresponding tongue, each cover plate having a tapered inset portion in which the tongue mounted thereto is free to pivot. Y K

2. A carpet sweeper comprising floor wheels arrangedV in pairs at opposite ends of a casing and rotatable on laterally pivotal and verticallyr displaceable hangers, a rotary brush mounted in the casing, a pulley on each end of the brush between the wheels of each pair and in drivhaving a frusto-triangular iinset portion beneath the point at which the tongue is mounted thereto, the'tongue being free to rotate in said inset portion, the rotary brush being journaled at oppositeends oi the tongues through a horizontally elongated slot in the corresponding cover plate, and means associated with said bail for changing therelative vertical positions of the wheels and brush. n

4. A' carpet sweeper comprising oor wheels arrangedin pairs at opposite ends of a casing and rotatablefon hangers mounted to the casing in laterally pivotal and vertically displaceable relationship, a spring connecting the wheelsof each pair so as to urge them together, a rotary brush mounted in the casing, a pulley on each end of the brush lbetween the wheels of' each pair and Vin driving contact'therewith, a bail having a separate leg pivotally mounted to each end of the casing and supporting an' elongated handle, a. stabilizer spring anchored at the two sides of each end of the casing, a lip extending inwardly from each of the legs of the bail adjacent the end thereof, the bottom surface of the lip resting on said spring and having a central concavesurface intermediate two convex surfaces, a cover plate aiiixed to Veach end of the casing and forming a housing with the ends of the casing forV the ll wheels and pulley, a tongue pivotally mounted in vertically slidable relationship to the upper part of each of said cover plates and extending downwardly therefrom to a point below the axis of rotation of the brush, the brush being journaled at either end to the corresponding tongue, each cover plate having a tapered inset iportion in which the tongue is free to pivot, and means operable by rotation of the bail for changing the relative vertical positions of the wheels and brush.

5. A carpet sweeper comprising oor wheels arranged in pairs at opposite ends o-f a casing and rotatable on hangers mounted to the casingr in laterally pivotal and vertically displaceable relationship, a spring connecting the wheels of Aeach pair so as to urge them together, a rotary brush mounted in the casing, a pulley on each end of the brush between the wheels of each pair and in driving contact therewith, a bail having a leg pivotally mounted to each end of the casing and supporting an elongated handle, a stabilizer spring anchored at the two sides of each end of the casing, lmeans forming a part of each leg of the bail for exerting a downward thrust on the central portion of each stabilizer spring,

a cover .plate aixed to each end of the casing f and forming a housing with the ends of the casing for the wheels and pulley, a tongue pivotally mounted in vertically slidable relationship to the upper part of each of said cover plates and extending downwardly therefrom to a point below the axis of rotation of the brush, the brush being journaled at either end to the corresponding tongue, each cover plate having a tapered inset portion in which the tongue mounted thereto is free to pivot, and means operable by rotation of the bail for changing the relative vertical positions of the wheels and brush.

6. A carpet sweeper according vto claim 5 wherein the means for changing the relative vertical positions of the wheels and brush comprises a pin projecting inwardly from each of said tongues, an eccentric cam mounted to each of the bail arms in engagement with 'the pin on the corresponding tongue and a suspension spring extending under said pin and urging the same upwardly against the cam.

7. Apparatus according to claim 2 wherein each stabilizer spring in anchored at one end `to an end of the casing in removable relationship and is held to the casing in slidable relationship at its opposite end.

8. A carpet sweeper comprising floor wheels arranged in pairs at opposite ends of a casing and rotatable on laterally pivotal and vertically displaceable hangers, a rotary'brush mounted in the casing and having a pulley at each end thereof in frictional contact between the Wheels of each pair, means for urging the respective wheels of each pair .toward the other and into contact with vthe pulley disposed therebetween, a bail having a separate leg pivotally mounted at its 'lower end 'to each end of the casing, the .two legs jointly supporting Van elongated-handle, a separatexstabilizer spring lying along and removably and slidably'anchored to each endof 'the casing, means forming a part of each leg of 'said bail for exerting a downward thrust on the Vcentral portion of each ,stabilizer spring, a cover plate afxed to each end of the casing .and forming a 'housing with the end of the casing for the wheels and pulley, each cover plate having a frustotriangular indented portion centrally spaced therein, a slot in the .upper edge of said indented portion of each housing, a separate tongue vpivotally mounted at its upper end to the inner face of each cover plate and projecting through the said slot to lie against and be laterally displaceab'le along the outer 'face of the 'inset 'portion ofthe plate, the brush A'being journaled at opposite ends to the lower end of the separate tongues, each 'cover plate having a laterally elongated slot through which the 'brush is journaled to the tongues and which permits the brush to shift laterally with the laterally pivotal tongues, and means'for changing the relative vertical positions of the wheels and brush.

9. A carpet sweeper comprising oor Wheels 4arranged in pairs at opposite ends of .a casing and rotatable on laterally jpivotal and vertically displaceable hangers, -arotary brush mounted in the casing, a pulley on'each end ofthe brush between the wheels of each pair and in driving contact therewith, means for urging Athe respective wheels of each pair toward the other and into contact with the pulley disposed therebetween, a bail having a leg pivotally mounted to each end of the casing and supporting an elongated handle, a cover plate affixed to each end of the casing and forming a housing with the ends of the Vcasing forV the wheels and pulley, ,a tongue pivotally mounted adjacent one of its ends in vertically slidable relationship to the upper Epart of each of said cover plates and extending downwardly therefrom to a point below the axis of rotation of the brush, the -brush .beingjjournaled at either end to the corresponding 'tongue at a point spaced from 'the point of pivotal mounting .of Vthe tongue so that the brush is 'free to move laterally to be in continuous driving contact with the Wheels.

.E'A Rl E R. SMITH.

References cited in @the nie of Auns patent UNITED STATES PATENTS Number yName f Date 525,721 Ru Ton Sept. 11,1894 v670,513 Johnson Mar.126., 1901 1,952,769 Mess;H Mar. 27,1934 2,011,261 Pullen Aug. 13, 1935 2,034,025 .Cummins Mar. I7, 193.6 2,121,880 Miller June 28, 1938 y2,436,460 Thiele Feb. 24, 194,8

FORETGN PATENTS Number Country nDate 168,611 Switzerland July 2 1934 476,932 Great Britain Dec. 20, 193.7 

